Submission #776692

#	Time	Username	Problem	Language	Result	Execution time	Memory
776692		GrindMachine	Uzastopni (COCI15_uzastopni)	C++17	80 / 160	16 ms	4660 KiB

uzastopni

// Om Namah Shivaya

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x, y) ((x + y - 1) / (y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i, n) for(int i = 0; i < n; ++i)
#define rep1(i, n) for(int i = 1; i <= n; ++i)
#define rev(i, s, e) for(int i = s; i >= e; --i)
#define trav(i, a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a, b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a, b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*

refs:
https://github.com/MetalBall887/Competitive-Programming/blob/master/Olympiad/COCI/COCI%2015-uzastopni.cpp
edi

*/

const int MOD = 1e9 + 7;
const int N = 100 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

int dp[N][N][N];
vector<int> adj[N];
vector<int> a(N);
bool avail[N][N];

void dfs(int u){
    trav(v,adj[u]){
        dfs(v);
    }
        
    memset(avail,0,sizeof avail);

    trav(v,adj[u]){
        rep1(l,N-1){
            for(int r = l; r < N; ++r){
                if(dp[v][l][r]){
                    if(l > a[u] or r < a[u]){
                        avail[l][r] = 1;
                    }
                }
            }
        }
    }

    avail[a[u]][a[u]] = 1;

    rev(l,N-1,1){
        dp[u][l][l] = avail[l][l];
        for(int r = l+1; r < N; ++r){
            if(avail[l][r]){
                dp[u][l][r] = 1;
            }
            else{
                for(int k = l; k < r; ++k){
                    dp[u][l][r] |= (dp[u][l][k] & dp[u][k+1][r]);
                }
            }
        }
    }

    rep1(l,N-1){
        for(int r = l; r < N; ++r){
            if(r < a[u] or l > a[u]){
                dp[u][l][r] = 0;
            }
        }
    }
}

void solve(int test_case)
{
    int n; cin >> n;
    rep1(i,n) cin >> a[i];
    rep1(i,n-1){
        int u,v; cin >> u >> v;
        adj[u].pb(v);
    }

    dfs(1);

    int ans = 0;
    rep1(l,N-1){
        for(int r = l; r < N; ++r){
            ans += dp[1][l][r];
        }
    }

    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

• Subtask 1: 80 / 160